Creation: Appeared in 1932 (after April) as a new U.S. Highway. It was attached to the entirety of SC 40, running from Tabor City to Green Sea, then Conway and Georgetown, continuing south to McClellanville, Mount Pleasant, and ending at US 17 (current US 52) in Charleston. The distance in 1932 was 130 miles.
Adjustments: In 1933, SC 40 was removed from US 701's routing.
In 1935, US 17 was added as a multiplex from Georgetown down to Charleston.
In 1950, US 701 was rerouted from Tabor City to come south through Loris to get to Conway. This eliminated SC 904 and was also some new primary routing. The old routing became today's SC 410. The new routing was 3 miles shorter.
Between 1962-64, US 701 was routed around Conway like it is today, leaving behind US 501 Business and SC 905.
About 1967, US 701 was rerouted onto the newly constructed Mt. Pleasant Bypass, leaving behind US 17-701 Business (I-526 spur and part of SC 703 today).
In 1992, US 701 south was truncated to its current Georgetown end, leaving behind US 17.
Improvements: Fully paved except for between Homewood and Green Sea when created in 1932; fully paved in 1934.
The first multilane section of US 701 appeared in 1958, on the south side of Mt. Pleasant around Shem Creek. US 701 became multilane between Conway and Homewood between 1962-64.
The next section to be upgraded was the Mt. Pleasant Bypass in 1967, which was extended north to SC 41 by 1970 and south to I-26 in Charleston.
By 1977, only a few more miles were 4-laned: around Awendaw, and an 8-mile stretch south of Georgetown.
By 1979, the 4-laning between Charleston and Georgetown was complete except for a couple miles south of McClellanville.
By 1982, US 701 was 4-lane continuously from Charleston to SC 51, plus a several miles in the Conway area.
Of course, with the elimination of 60 miles of US 701, only a handful of miles are multilane today.
Comment: US 701 is a quiet ride west of the Waccamaw River, and can be used as part of an overall Grand Strand Bypass (along with SC 90).
US 701 was already not well posted south of Georgetown by the mid-70's. There were no US 701 signs on I-26, but there was one on a BGS at the US 17 Business split to Mt. Pleasant. The last SB sign used to be at the foot of the Mount Pleasant side of the Cooper River Bridge.
After the truncation, the SB sign near Charleston remained for a time, and a US 701 shield remained past the year 2000 (status uncertain today) on US 52 NB a few blocks north of the end of I-26 (the shield directed a right turn to go back to US 17-701 via Morrison Dr). Last year there was still a small overhead green sign at the jct of US 17-17A-701 in Georgetown (you see it on US 17 SB approaching the intersection) saying US 17-701 to Charleston.
US 701 really hasn't been rebuilt that much, especially on its current routing. There had been a little between Georgetown and Charleston, notably today's S-10-9 near McLellanville. The original routing through Mount Pleasant is not clear either.

BUSINESS

From: (Horry County) To: North Carolina State Line at Tabor City, NC (Horry County)Total Length: 0.1 miles (maybe not even that far)

ROUTE LOG
US 701: 0 - 0
NC STATE LINE: 0.1 - 0.1

Creation: Appeared by 1958 according to NC Official Maps. However, North Carolina did not use any business designations until 1960, so this may have been US 701 ALT for a couple years.
Adjustments: None
Improvements: Fully paved from inception with no multilane sections.
Comment: US 701 Business for Tabor City is one of 2 Business routes in South Carolina to cross a state line (US 25 Bus North Augusta is the other). This is North Carolina's only example to do this.
US 701 Business was not part of original SC 40 but was instead part of SC 904.

US
701 Business Decommissioned

Previous US 701 Business:

US 701 Business: Appeared about 1967 as Mount Pleasant was bypassed to the north. This route had been part of SC 40 originally. Used Georgetown Hwy and Coleman Blvd. The Coleman Blvd section was multilane. By 1975, there were no US 701 Business signs that I could recall anywhere. In any case, US 701 Business was removed by 1992 in favor of I-526 Business SPUR and an extended SC 703.